chore(tools): show demo in live window (#1138)

tools/demo.py

@@ -211,18 +211,19 @@ def imageflow_demo(predictor, vis_folder, current_time, args):
     width = cap.get(cv2.CAP_PROP_FRAME_WIDTH)  # float
     height = cap.get(cv2.CAP_PROP_FRAME_HEIGHT)  # float
     fps = cap.get(cv2.CAP_PROP_FPS)
-    save_folder = os.path.join(
-        vis_folder, time.strftime("%Y_%m_%d_%H_%M_%S", current_time)
-    )
-    os.makedirs(save_folder, exist_ok=True)
-    if args.demo == "video":
-        save_path = os.path.join(save_folder, os.path.basename(args.path))
-    else:
-        save_path = os.path.join(save_folder, "camera.mp4")
-    logger.info(f"video save_path is {save_path}")
-    vid_writer = cv2.VideoWriter(
-        save_path, cv2.VideoWriter_fourcc(*"mp4v"), fps, (int(width), int(height))
-    )
+    if args.save_result:
+        save_folder = os.path.join(
+            vis_folder, time.strftime("%Y_%m_%d_%H_%M_%S", current_time)
+        )
+        os.makedirs(save_folder, exist_ok=True)
+        if args.demo == "video":
+            save_path = os.path.join(save_folder, os.path.basename(args.path))
+        else:
+            save_path = os.path.join(save_folder, "camera.mp4")
+        logger.info(f"video save_path is {save_path}")
+        vid_writer = cv2.VideoWriter(
+            save_path, cv2.VideoWriter_fourcc(*"mp4v"), fps, (int(width), int(height))
+        )
     while True:
         ret_val, frame = cap.read()
         if ret_val:
@@ -230,6 +231,9 @@ def imageflow_demo(predictor, vis_folder, current_time, args):
             result_frame = predictor.visual(outputs[0], img_info, predictor.confthre)
             if args.save_result:
                 vid_writer.write(result_frame)
+            else:
+                cv2.namedWindow("yolox", cv2.WINDOW_NORMAL)
+                cv2.imshow("yolox", result_frame)
             ch = cv2.waitKey(1)
             if ch == 27 or ch == ord("q") or ch == ord("Q"):
                 break